I have a droid 4 but believe this is a widespread problem with Jellybean update. About 3 months ago I noticed when using Bluetooth device that the speakerphone was kicking in simultaneously after a minute or so. So sound would be both received and transmitted through Bluetooth and speaker resulting in interference. I would have to switch to handpiece to continue. I get this with 3 different Bluetooth devices and believe it is phone related. i see postings everywhere and find it hard to believe Google hasn't provided a fix but it appears that way. a major hassle to say the least being it affects safety and use of hands free technology. Anyone with a fix for this?